1. Field of the Invention
The present invention concerns machines for multiple treatment, especially sanding of ski soles.
2. Description of the Prior Art
Repair and maintenance of ski soles entail multiple treatments which can be combined or carried out separately depending on the required results, and which include:
resin-coating or partial stopping of the ski sole, carried out dry, rough or finish wet sanding of the ski sole using a strip of abrasive material, PA1 rough or finish wet grinding the ski sole using a grinding wheel periodically dressed using a diamond tool, PA1 wet or dry edge grinding generally using a strip of adhesive material, possibly using a diamond grinding wheel, PA1 dry deburring of the ground edge wires using a very fine abrasive disk or drum, PA1 waxing the sole, usually carried out dry by applying hot wax or spraying wax paste, PA1 dry polishing the wax using a non-abrasive polishing disk or drum. PA1 the tools are disposed and oriented so that their working faces are their lower faces, PA1 a plurality of tools are offset transversely relative to each other, PA1 the means for holding and displacing the skis are adapted to hold the skis with their sliding soles facing upwards and to move them under the tools by reciprocating movement in longitudinal translation in the lengthwise direction of the skis, by transverse movement in translation to move the skis selectively in line with one of the transversely offset tools and in vertical translation to selectively move the skis against or away from the tools. PA1 a carriage mobile transversely on transverse guides of the frame and driven by drive means having control means, PA1 a longitudinal beam sliding vertically on vertical guides of the carriage and moved by a jack controlled by said control means, and PA1 a box-section open at the top and shaped to receive and retain at least one ski with its sliding sole facing upwards, the box-section being oriented longitudinally and driven longitudinally on the longitudinal beam by longitudinal reciprocating drive means.
These treatments can be carried out on separate machines each carrying out one kind of treatment, so that seven machines are required in all. For example, document DE-U-90 01 959 describes a ski sole grinding machine with a diamond grinding wheel that is moved longitudinally along a fixed ski; document CH-A-254 024 describes a machine for milling the running groove on the ski sole using a milling tool which is moved longitudinally along a fixed ski; document DE-A-2 209 407 describes a machine for resin-coating the ski sole using a device for recurring the running groove, but with no grinding device, the recurring tool being moved along the fixed ski. These prior art machines require the operator to move along the successive machines in order to pass the ski through them, the ski being driven in one direction only.
Document DE-C-641 445 describes a machine for multiple machining of the top surface of skis using a plurality of fixed cutting tools across which the ski is moved longitudinally with its sole facing downwards. All the machining operations are carried out with the ski travelling at the same speed. The machine does not allow machining or other treatment at different speeds.
With a view to increasing productivity robotized machines have been proposed in which the additional equipment comprises a motorized arm supporting the ski with the sole facing downwards and reciprocating it across the tool. The evolution of such robots has led to designs featuring ever more operations conducted "in line", the workstations being disposed one after the other. The most comprehensive robots can now carry out all the operations mentioned above.
A first drawback of robotized machines is that their in-line design results in a very long machine, each unit being on average 1 m long and wide, to which must be added room for the ski on entering and leaving the machine, i.e. twice 2 m. Accordingly, robots combining the finishing operations, namely grinding, edge grinding, deburring, waxing and wax polishing are about 7 m long by 1.5 m wide. Robots combining all of the operations mentioned above are in the order of 7 m long by 3.5 m wide. The problems of accommodating such machines in the workshops of sporting goods stores which are not designed to accommodate such equipment hardly need emphasizing.
A second drawback is that the in-line design requires that all the units operate with the ski moving forward at the same speed, which is a drawback from the technical point of view: the optimum speed differs from one treatment to another, with the resin-coating speed being around 2 m/min, finish grinding and sanding requiring speeds in the order of 6 m/min to 7 m/min for optimum results, and the other treatments being advantageously carried out at speeds in the order of 4 m/min to 5 m/min. The treatment results are worse if the same speed is used throughout.
A third drawback of robotized machines is a lack of flexibility. Although it is possible to program some only off the treatments previously mentioned, by retracting the unwanted units, the in-line design nevertheless entails the total transit time of the skis through all the stations, making the system less user-friendly.
In prior art robotized machines, the sole of the ski faces downwards and the ski is driven from above. This requires a motorized arm equipped with accessories to support the ski firmly. A first device for this purpose comprises flexible suction shoes which hold the ski from above. Problems can arise with skis which do not have a flat top. If the device accidentally releases the ski it drops onto the workstation which can be very dangerous in the case of a tool with high tangential speed of rotation, in the order of 20 m/s to 25 m/s, for example. A second device includes a mechanism shaped like the sole of a ski boot which fits into the ski bindings and is attached to the motorized arm. A device of this kind cannot be used on skis with no bindings. The ski is also supported irregularly, in particular because of the flexibility of its ends, so that the finish on the soles is less than exemplary.
One problem encountered in prior art machines results from the need for spraying of large amounts of water for wet sanding and grinding. The reason for spraying the water is to prevent the ski sole overheating. The resulting considerable splashing of water, although tolerable in a factory, is not compatible with the necessarily protected environment of a sporting goods store. Being splashed with water is also harmful to some tools of the machine, especially the system for dressing the grinding wheel using a diamond tool, which is usually a high-precision mechanism which must be protected from splashing with water and swarf.
The problem to which the present invention is addressed is that of defining a new architecture for machines for multiple treatment of ski soles which have reduced overall size and reduced cost, offer optimum flexibility in terms of selection of partial treatments, enhance the quality of sanding and other treatments and are very easy to use, especially with regard to handling and fitting the skis.
One aim of the invention is to provide a multiple treatment machine which is compatible with the environment of the repair workshops of sporting goods stores.